<div class="left-nav" style="margin:20px">

    <ul class="layui-nav layui-nav-tree" lay-filter="test">
<!-- 侧边导航: <ul class="layui-nav layui-nav-tree layui-nav-side"> -->
  <li class="layui-nav-item layui-nav-itemed">
    <a href="javascript:;">默认展开</a>
    <dl class="layui-nav-child">
      {volist name="sub_menu_list" id="vo"}
                            <dd>
                                <a hreft='{$vo.url}'>
                                   <i class="layui-icon layui-icon-{$vo.icon}"></i>

                                    <cite>{$vo.title}</cite></a>
                            </dd>
                            {/volist}
      <dd><a href="javascript:;">选项1</a></dd>
      <dd><a href="javascript:;">选项2</a></dd>
      <dd><a href="">跳转</a></dd>
    </dl>
  </li>
  <li class="layui-nav-item">
    <a href="javascript:;">解决方案</a>
    <dl class="layui-nav-child">
      <dd><a href="">移动模块</a></dd>
      <dd><a href="">后台模版</a></dd>
      <dd><a href="">电商平台</a></dd>
    </dl>
  </li>
  <li class="layui-nav-item"><a href="">产品</a></li>
  <li class="layui-nav-item"><a href="">大数据</a></li>
</ul>
           
                

        </div>
        <!-- <div class="x-slide_left"></div> -->